Self-cleaning air duct



Oct. 1, 1968 c. M. POOLE SELF-CLEANING AIR DUCT v2 Sheets-Sheet 1 Filed Feb. 16, 1966 INVENTOR. 0744 9455 M P0015 Oct. 1, 1968 c. M. POOLE 3,403,702

SELF-CLEANING AIR DUCT Filed Feb. 16,' 1966 2 Sheets-Sheet 2 IN VEN TOR. K M/P455 M P0045 WWW United States Patent Stevens & Co., Inc., New York, N.Y., a corporation of Delaware Filed Feb. 16, 1966, Ser. No. 527,888 13 Claims. (Cl. 138-37) ABSTRACT OF THE DISCLOSURE This invention relates to an air duct which prevents the accumulation of dust and lint on the top thereof comprising an enclosed conduit having a top, a portion of said top defining an opening therein; deflecting means positioned in said opening and depending a short distance into said conduit for deflecting a minor portion of air flowing therein into an upward direction through said opening; a hood having suitable apertures therein positioned adjacent said opening on the top of said conduit for restoring the horizontal direction of said air flow outside of said conduit and across the top thereof whereby the constant flow of air along the top and outside of said conduit prevents the accumulation of lint and dust on the top thereof.

This invention relates to an air duct. More particularly this invention relates to air ducts which are commonly used in textile plants where fibrous or lint producing manufacturing processes are performed.

In textile plants, as Well as in similar facilities, air ducts generally extend through the plant to provide cool as well as warm air at appropriate times. Because of the nature of the work, dust and lint are prevalent. This dust and lint presents a problem in that it settles upon the top of the duct, which is generally quite elevated. The dust and lint must beremoved periodically in order to prevent the accumulated lint from falling from the top of the air duct into the machinery below and thereby damaging the quality of the product being manufactured, e.g. woven cotton or woolen goods.

Previous methods of removing accumulated lint involved employing men to climb ladders and physically remove the lint through the use of brushes or compressed air. These prior lint and dust removal methods involved 'a safety hazard to the employees who climbed such ladders as well as additional cost in employing such men to perform the function of lint removal.

An object of this invention therefore is to provide a self cleaning air duct. 'Another object is to eliminate the safety hazard and economic disadvantage entailed in removing dust and lint from thetop of an air duct.

This invention contemplates structures such as an air duct which prevents the accumulation of dust and lint on the top thereof comprising an enclosed conduit having a top, a portion of said top defining an opening therein, means mounted adjacent said opening and associated therewith to deflect a minor portion of air moving through said conduit and passing through said opening across and along the outside of said top to dislodge lint and dust therefrom.

This invention also contemplates a process for preventing the accumulation of lint and dust on the top of an air duct comprising flowing air in a substantially horizontal manner through an enclosed conduit, deflecting a minor portion of the air flow to an upward direction and through an opening in the top of said conduit, restoring the horizontal direction of said air flow outside of said conduit, and across the top thereof whereby the constant flow of air across the top of said conduit and outside of said conduit Patented Oct. 1, 1968 "ice prevents the accumulation of lint and dust on the top thereof.

In the drawing FIGURE 1 is an isometric view of my invention;

FIGURE 2 is a cross-sectional view along the line 2-2 of FIGURE 1;

FIGURE 3 is a cross-sectional view along the line 3-3 of FIGURE 2;

FIGURE 4 is a fragmentary isometric view showing a single elongated orifice on a side of the hood;

FIGURE 5 is a fragmentary isometric view showing a plurality of orifices and directional louvers on two sides of the hood;

FIGURE 6 is a cross-sectional view taken along the line 66 of FIGURE 5;

FIGURE 7 is a plan-sectional view taken along the line 7-7 of FIGURE 6; and

FIGURE 8 is a fragmentary isometric view showing awning-like directional louvers.

Referring now to FIGURES 1 and 2 of the drawings, the air duct 3 comprising an enclosed conduit '5 which has an opening 7 for the egress of air therefrom. A baflle 9 extends for a short distance into the conduit 5 and is connected to the top 11 of said conduit near the opening 7. The bafile 9 functions to deflect a minor portion of the air flowing through the conduit 5 upward and outside of said conduit 5. For this purpose, the baffle 9 is generally located adjacent the far side of the opening 7 relative to the flow of air in the conduit 5.

A hood 15 encloses the opening. The hood has a side 17 which defines orifices 19, therein. When a portion of the air flow is deflected by the baflle 9 through the opening 7 in the top 11 of the conduit 5, it enters the hood 15 and then exits through orifices 19, in the side 17 of the hood 15 and across the outside top 11 of the conduit 5. In this manner, a constant scavenging blast of air is kept flowing across the outside top 11 of the conduit 5 and prevents lint and dust from accumulating thereon.

The opening 7 in the top 11 of the conduit 5 may be as large or as small as desired. However, as a general rule it is preferred that the opening besubstantially larger than the total area of orifices 19, through which air is blown across the outside top 11 of the conduit 5. In this manner, the stream of air which prevents the lint and dust from accumulating will generally be more forceful and more effective than will a stream of air which has been passed through an opening in the conduit which has a total area equal to or less than the total orifice area.

The baffle 9 may extend for a short distance into the conduit 5 at an angle of up to about relative to the axis formed by the conduit top 11 and the opening 7. It has been found that an excellent degree of air deflection from the conduit 5 is obtained when the baffle 9 is an angle of 45 relative to said axis.

The baflle 9 need only extend into the conduit 5 for a short distance to provide the desired air deflection. For example, satisfactory air deflection is provided by a baffle 9 which extends into the conduit 5 for a distance of one one-hundredth the height of the conduit 5. If desired, the baflle 9 may extend for a greater distance such as one-quarter the height of the conduit 5 and may even extend further depending upon the degree of air deflection desired.

Instead of a bafile and hood, alternative means (not shown) may be provided for causing a portion of the air moving through the conduit to flow out of the conduit and across the outside top of the conduit. For example, a plate may be provided which is connected to the conduit along the periphery of the near side of an opening relative to the direction of the air flow in the conduit. The plate would be spaced above and across theopening. In this manner, some of the air flowing through the conduit will be impelled through the opening and directed by the plate across the top of the conduit thereby preventing lint and dust from accumulating thereon.

The orifices 19, are preferably located on the side 17 of the hood 15 adjacent the far side of the opening 7 relative to the direction of the air flow in the conduit 5. Alternatively,-as seen in FIGURES through 8, orifices 19 and 19' may be provided on either or both sides 17 and 17 of the hood so that the top 11 of the conduit 5 will be cleaned by a scavenging blast of air across its top 11 in the direction of the air flowing through the conduit 5 as well as in the opposite direction.

The bottom of the orifice may be located level (not shown) with the outside top of the conduit or slightly above. If desired, the orifice may comprise a long slit like orifice (FIGURES 4 and 8) and 25' (FIGURE 8) or a plurality of shorter adjacent orifices 19 (FIGURE 1) and 19 and 19' (FIGURE 5).

In another embodiment, and particularly when a plurality of orifices are utilized, directional louvers may be provided to direct the scavenging blast of air across the top of the conduit in a number of difierent directions to assure that lint and dust will not accumulate in any one small area on the top of the conduit which may be out of reach of a less directed scavenging blast of air.

The hood may extend completely across the Width of the top of the conduit or for a shorter distance. When the hood extends across the top of the conduit for less than five-sevenths of the width of the conduit, then directional louvers 27 (FIGURE 5) as aforedescribed may often prove advantageous although such directional louvers 27 need not necessarily be employed. Additionally, di- :rectional louvers 29 (FIGURE 8) may be provided to direct the air fiow downward against the top 11 of the conduit 5. In this manner, a greater than normal amount of the scavenging blast of air is directed across the surface of the top 11 of the conduit 5.

The conduit itself may have a round or rectangular cross section. Whether the conduit is round or rectangular is of no consequence in practicing this invention.

The baffle 9 and hood 15 are preferably spaced at intervals along the conduit sufiicient to cause a scavenging blast of air to extend across the top 11 of the conduit 5 to the next hood.

The air duct 3 itself may be made of any metal which is commonly used for this purpose. These metals, such as aluminum, tin, galvanized tin, etc. are well-known in the art and the invention should not be construed as limited to any particular material.

The invention itself provides a readily effective means of preventing lint and dust from accumulating on the top of the air duct. It, thus eliminates the necessity of an employee climbing a ladder to remove such accumulations and therefore eliminates not only the safety hazards involved, but also the additional cost involved in the removal of the lint and dust.

While this invention has been described in terms of certain preferred embodiments, the invention is not to be construed as limited except as set forth in the following claims.

What is claimed is:

1. An air duct which prevents the accumulation of dust and lint on the top thereof comprising an enclosed conduit having a top, a portion of said top defining an opening therein; deflecting means positioned in said opening and extending for a short distance into said conduit for deflecting a minor portion of air flowing through said conduit upward and outside of said conduit; covering means mounted on the top of said conduit and adjacent said opening, said covering means having suitable apertures therein for restoring the horizontal direction of said air flow outside and across the top of said conduit whereby the constant flow of air along the top of said conduit prevents the accumulation of lint and dust on the top of said duct.

2. An air duct according to claim 1 wherein said defiecting means includes a baffie depending into said conduit and connected to said top at a point adjacent said opening.

3. An air duct according to claim 1 wherein said covering means is a hood connected to said top adapted to cover said opening, said hood having a side defining an orifice therein.

4. An air duct according to claim 3, wherein said side defining said orifice is adjacent the far side of said opening relative to said air flow in said conduit.

5. An air duct according to claim 3, wherein said side defining said orifice is at substantially a right angle to said top.

6. An air duct according to claim 3, wherein said side defines a plurality of orifices.

7. An air duct according to claim 3, wherein said side defines an orifice spaced from and above said top of said conduit.

8. An air duct according to claim 3, wherein said side defining said orifice has a directional louver adjacent said orifice.

9. An air duct which prevents the accumulation of dust and lint on the top thereof comprising an enclosed conduit having a top, a portion of said top defining an opening therein, a baffle depending into said conduit and connected to said top adjacent said opening and for deflecting a minor portion of the flow of air through said conduit to an upward direction, a hood connected to said top and over said opening, said hood having a side defining an orifice therein, whereby when said bafiie deflects said air flow upwardly, said air flows upwardly into said hood, through said orifice and across the top of said air duct to prevent lint and dust from accumulating thereon.

10. A process for preventing the accumulation of lint and dust on the top of an air duct comprising flowing air in a substantially horizontal manner through an enclosed conduit, deflecting a minor portion of the air fiow to an upward direction and through an opening in the top of said conduit, restoring the horizontal direction of said air flow outside of said conduit, and across the top thereof whereby the constant flow of air across the top of said conduit and outside of said conduit prevent-s the accumulation of lint and dust on the top thereof.

11. A process according to claim 10, including flowing said air outside of said conduit through a plurality of orifices and across said top of said conduit.

12. A process according to claim 11, including guiding the flow of air through said orifices in varying directions across said top of said conduit.

13. A process according to claim 10, including flowing said air through said orifice and across the outside top of said conduit in the same general direction as the flow of air through said conduit.

References Cited UNITED STATES PATENTS 2,183,174 12/1939 Smith 138-39 2,477,824 8/1949 Reiss 9840 2,804,007 8/1957 Kurth 9840 FOREIGN PATENTS 856,127 12/1960 Great Britain.

LAVERNE D. GEIGER, Primary Examiner.

B. KILE, Assistant Examiner. 

